Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c5cb5a2d authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Ingo Molnar
Browse files

kprobes: Clean up insn_pages by using list instead of hlist 



Use struct list instead of struct hlist for managing
insn_pages, because insn_pages doesn't use hash table.

Signed-off-by: default avatarMasami Hiramatsu <mhiramat@redhat.com>
Acked-by: default avatarAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
LKML-Reference: <20090630210814.17851.64651.stgit@localhost.localdomain>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 4a2bb6fc

kernel/kprobes.c

+11 −19
Original line number Diff line number Diff line
@@ -103,7 +103,7 @@ static struct kprobe_blackpoint kprobe_blacklist[] = { 
#define INSNS_PER_PAGE	(PAGE_SIZE/(MAX_INSN_SIZE * sizeof(kprobe_opcode_t)))



struct kprobe_insn_page {

	struct hlist_node hlist;

	struct list_head list;

	kprobe_opcode_t *insns;		/* Page of instruction slots */

	char slot_used[INSNS_PER_PAGE];

	int nused;
@@ -117,7 +117,7 @@ enum kprobe_slot_state { 
};



static DEFINE_MUTEX(kprobe_insn_mutex);	/* Protects kprobe_insn_pages */

static struct hlist_head kprobe_insn_pages;

static LIST_HEAD(kprobe_insn_pages);

static int kprobe_garbage_slots;

static int collect_garbage_slots(void);
@@ -152,10 +152,9 @@ static int __kprobes check_safety(void) 
static kprobe_opcode_t __kprobes *__get_insn_slot(void)

{

	struct kprobe_insn_page *kip;

	struct hlist_node *pos;



 retry:

	hlist_for_each_entry(kip, pos, &kprobe_insn_pages, hlist) {

	list_for_each_entry(kip, &kprobe_insn_pages, list) {

		if (kip->nused < INSNS_PER_PAGE) {

			int i;

			for (i = 0; i < INSNS_PER_PAGE; i++) {
@@ -189,8 +188,8 @@ static kprobe_opcode_t __kprobes *__get_insn_slot(void) 
		kfree(kip);

		return NULL;

	}

	INIT_HLIST_NODE(&kip->hlist);

	hlist_add_head(&kip->hlist, &kprobe_insn_pages);

	INIT_LIST_HEAD(&kip->list);

	list_add(&kip->list, &kprobe_insn_pages);

	memset(kip->slot_used, SLOT_CLEAN, INSNS_PER_PAGE);

	kip->slot_used[0] = SLOT_USED;

	kip->nused = 1;
@@ -219,12 +218,8 @@ static int __kprobes collect_one_slot(struct kprobe_insn_page *kip, int idx) 
		 * so as not to have to set it up again the

		 * next time somebody inserts a probe.

		 */

		hlist_del(&kip->hlist);

		if (hlist_empty(&kprobe_insn_pages)) {

			INIT_HLIST_NODE(&kip->hlist);

			hlist_add_head(&kip->hlist,

				       &kprobe_insn_pages);

		} else {

		if (!list_is_singular(&kprobe_insn_pages)) {

			list_del(&kip->list);

			module_free(NULL, kip->insns);

			kfree(kip);

		}
@@ -235,14 +230,13 @@ static int __kprobes collect_one_slot(struct kprobe_insn_page *kip, int idx) 


static int __kprobes collect_garbage_slots(void)

{

	struct kprobe_insn_page *kip;

	struct hlist_node *pos, *next;

	struct kprobe_insn_page *kip, *next;



	/* Ensure no-one is preepmted on the garbages */

	if (check_safety())

		return -EAGAIN;



	hlist_for_each_entry_safe(kip, pos, next, &kprobe_insn_pages, hlist) {

	list_for_each_entry_safe(kip, next, &kprobe_insn_pages, list) {

		int i;

		if (kip->ngarbage == 0)

			continue;
@@ -260,19 +254,17 @@ static int __kprobes collect_garbage_slots(void) 
void __kprobes free_insn_slot(kprobe_opcode_t * slot, int dirty)

{

	struct kprobe_insn_page *kip;

	struct hlist_node *pos;



	mutex_lock(&kprobe_insn_mutex);

	hlist_for_each_entry(kip, pos, &kprobe_insn_pages, hlist) {

	list_for_each_entry(kip, &kprobe_insn_pages, list) {

		if (kip->insns <= slot &&

		    slot < kip->insns + (INSNS_PER_PAGE * MAX_INSN_SIZE)) {

			int i = (slot - kip->insns) / MAX_INSN_SIZE;

			if (dirty) {

				kip->slot_used[i] = SLOT_DIRTY;

				kip->ngarbage++;

			} else {

			} else

				collect_one_slot(kip, i);

			}

			break;

		}

	}